Codex Comes to Windows: Native Sandbox, PowerShell, and No WSL Required

OpenAI released the Codex app for Windows on March 4, 2026, one month after the macOS version. The Mac launch pulled over a million downloads in its first week. More than 500,000 developers signed up for the Windows waitlist.

The app is available now through the Microsoft Store and requires Windows 10 build 19041.0 or later.

Why It Took a Month

Building a coding agent for Windows isn’t just a recompile. The biggest engineering challenge was the sandbox. On macOS, Codex uses the platform’s built-in sandboxing and process isolation. Windows doesn’t have an equivalent out of the box, so OpenAI worked with Microsoft to build one from scratch.

The result is an open-source, native Windows sandbox that enforces OS-level isolation through three mechanisms:

Restricted tokens: Each agent process runs with reduced privileges, preventing unrestricted access to external services
Filesystem ACLs: File modifications are limited to designated worktrees, so an agent can’t write outside its assigned project directory
Dedicated sandbox users: Every agent gets its own system user, reducing lateral movement risk if something goes wrong

This is notably different from the “run it in WSL” approach that most AI coding tools take on Windows. Codex agents run natively in PowerShell. No virtual machines. No Linux subsystem. Just Windows.

OpenAI open-sourced the sandbox components specifically so security researchers and IT teams can audit the isolation model. For enterprises evaluating Codex, that’s a meaningful distinction.

What’s In the App

The Windows version ships with the same feature set as macOS:

Multi-agent support. You can run multiple agents in parallel, each working on different tasks across different projects. Each agent maintains its own state and history, so you can pause and resume long-running work without losing context.

Three execution modes. Every thread can run in Local (direct project work), Worktree (isolated Git branch), or Cloud (remote environment) mode. Worktrees are the interesting one: each task gets its own Git worktree, and you review diffs before anything merges into your codebase.

Automations. Schedule and delegate repeatable tasks like error triage, CI failure summarization, or daily code change reports. Automations run in dedicated background worktrees, so they can’t interfere with your active work.

Skills. Modular instruction packages that extend what agents can do: image generation, deployment, test triage, and more. You can browse available skills in a sidebar and install new ones from the marketplace.

Integrated terminal. Scoped to the current project or worktree, accessible via Cmd+J (or Ctrl+J on Windows). Full PowerShell support, not a shim on top of bash.

Cross-platform session continuity. This is the one that matters for developers who switch between machines. Session history is saved to your OpenAI account, so you can start work on a Mac and pick it up on Windows without losing anything.

Editor Integration

The Windows release supports syncing with several editors: Visual Studio, VS Code, Rider, PhpStorm, Sublime Text, and terminal environments like Git Bash and Cmder. When the Codex IDE Extension is running in the same project, the app automatically tracks which files you’re viewing for context.

Who Gets Access

Codex on Windows is available across all ChatGPT account tiers: Free, Go, Plus, Pro, Business, Enterprise, and Edu. The same account works across the app, CLI, IDE extension, and cloud, so there’s no separate Codex subscription to manage.

To celebrate the launch, OpenAI is giving paid ChatGPT subscribers double the normal Codex rate limit through April 2, 2026. Free and Go users can try Codex for the first time during this window.

The Numbers

According to OpenAI, Codex has crossed 1.6 million weekly active users across all platforms. The company cites the 2025 Stack Overflow Developer Survey, which found that roughly 50% of developers use Windows professionally and over 55% use it personally. That’s a large audience that was locked out of the desktop app until now.

The Windows launch also brings feature parity to the CLI. Version 0.110.0, released the same day, added a direct Windows installer script to published release artifacts. And version 0.106.0 (February 25) had already started publishing CLI releases to winget, so Windows developers can install and update the CLI through their normal package manager.

Security and Governance

Two features stand out for teams and enterprises:

Default least-privilege. Agents are limited to the folder and branch they’re assigned to. Any operation outside that scope requires explicit permission.

Configurable approval rules. Teams can pre-approve trusted actions for specific projects, which reduces repetitive permission prompts without giving agents blanket access. All operations maintain audit trails.

What This Means

The Codex Windows launch closes the biggest gap in OpenAI’s developer tools strategy. With Mac, Windows, CLI, IDE extensions, and cloud all sharing a single account and session history, OpenAI now has the widest platform coverage of any AI coding agent.

The real test is whether the Windows sandbox holds up. Open-sourcing it was the right call for building trust, but it’s a v1 product running in a diverse ecosystem of antivirus software, enterprise policies, and legacy Windows configurations. Expect some rough edges in the early weeks.

For the competitive landscape: Claude Code and Gemini CLI both work on Windows through the terminal, but neither offers a native desktop app with this level of integration. Cursor and Windsurf have desktop apps on Windows, but they’re IDE-based rather than agent-based. Codex is carving out its own lane: a standalone agent app with multi-project orchestration, native sandboxing, and platform-level continuity.

Sources: OpenAI: Introducing the Codex app, Codex Windows documentation, Codex Changelog, Thurrott: OpenAI Releases Codex App for Windows, WindowsForum: OpenAI Codex Arrives on Windows, WinBuzzer: OpenAI Brings Codex AI Coding App to Windows